Patents by Inventor Krishna Balachandran

Krishna Balachandran has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7054346
    Abstract: A wireless endpoint employs frequency hopping for communicating signals in a wireless communications system. Over a time period T, the wireless endpoint performs pseudo-random selection of a frequency from a hopping set of N frequencies such that over at least a portion of the time period T, the frequency selection is constrained to less than the N frequencies.
    Type: Grant
    Filed: May 7, 2001
    Date of Patent: May 30, 2006
    Assignee: Lucent Technologies Inc.
    Inventors: Krishna Balachandran, Joseph H Kang, Kumud K Sanwal, James Paul Seymour
  • Patent number: 7020185
    Abstract: One example of symbol or bit error probability estimation in a communication system using soft decision information determines soft decision metric(s) for each symbol that is received over a communication channel and employs the soft decision metric(s) to obtain an estimate of symbol or bit error probability.
    Type: Grant
    Filed: November 28, 2000
    Date of Patent: March 28, 2006
    Assignee: Lucent Technologies Inc.
    Inventors: Krishna Balachandran, Sanjiv Nanda
  • Patent number: 7006477
    Abstract: A system and method for providing wireless time division multiplexed communications in which time is divided into a plurality of frames and each frame is divided into N data bursts, which has a first multiplexer defining a channel as a series of bursts that occur periodically every N bursts once per frame; a second multiplexer defining a sub-channel as every Mth burst of said channel; and a transmitter transmitting said channel and sub-channel from a first station to a second station. A new interleaving 0246/1357 method is used by the system which is just as good as the known 0123/4567 method when ideal frequency hopping is used, and 0246/1357 has better performance when non-ideal frequency hopping or no frequency hopping is used.
    Type: Grant
    Filed: August 30, 2000
    Date of Patent: February 28, 2006
    Assignee: Lucent Technologies Inc.
    Inventors: Krishna Balachandran, Richard Paul Ejzak, Sanjiv Nanda
  • Patent number: 6996083
    Abstract: A method and system for reducing delay in wireless communications by use of a burst based access and assignment system. The method for setting up a communication channel uses short burst(s) (essentially a slot of a time frame). Time is saved by keeping the uplink and downlink channels flexible and independent of each other. Thus less time is used trying to fit all requests and responses into constrained choices as in previous protocols. The result is less delay to the mobile user and greater usage density for the wireless service provider.
    Type: Grant
    Filed: August 30, 2000
    Date of Patent: February 7, 2006
    Assignee: Lucent Technologies Inc.
    Inventors: Krishna Balachandran, Sanjiv Nanda, Konstantinos Samaras
  • Patent number: 6990104
    Abstract: Uplinked and downlinked transmissions in an interference-limited system, such as a cellular network, are prioritized and authorized by channel quality/data rate to minimize interference.
    Type: Grant
    Filed: August 3, 2000
    Date of Patent: January 24, 2006
    Assignee: Lucent Technologies Inc.
    Inventors: Krishna Balachandran, Kirk K. Chang, Sanjiv Nanda
  • Patent number: 6975611
    Abstract: A method and communication device for media access control feedback over a packet channel divided in channel time slots is provided. The channel time slots are divided into sub-channel time slots. A packet channel feedback field associated with each sub-channel time slot is defined. Acknowledgments are indicated using the packet channel feedback field. An active mobile identity associated with an active mobile station may be assigned which would then be included in the packet channel feedback field. A plurality of active mobile identities may be assigned and some of the active mobile identities may be reserved for special functions. The assigned active mobile identity is used, among other things, to identify an active mobile station to receive packet data signals. The active mobility identity is invalidated after one transaction of packet data signals or invalidated after a short number of such transactions.
    Type: Grant
    Filed: March 3, 2000
    Date of Patent: December 13, 2005
    Assignee: Lucent Technologies Inc.
    Inventors: Krishna Balachandran, Subrahmanyam Dravida, Richard P. Ejzak, Sanjiv Nanda, Shiv M. Seth, Stanley Vitebsky
  • Patent number: 6963544
    Abstract: A system for providing statistical multiplexing of speech, other real-time data services and non-real-time data services for point to point and point to multipoint communications. The system has fast access and assignment procedures that allow the multiplexing of real-time, delay-critical data services with non-real-time data services. Continuity of periodic control channels across speech talkspurt and silence periods for conversational voice is maintained to carry signal measurement reports, channel quality feedback, and “comfort” noise information between different parts of the system.
    Type: Grant
    Filed: August 31, 2000
    Date of Patent: November 8, 2005
    Assignee: Lucent Technologies Inc.
    Inventors: Krishna Balachandran, Cristian Demetrescu, Richard Paul Ejzak, Sanjiv Nanda, Hong Xie
  • Publication number: 20050207365
    Abstract: Rather than transmitting a large full Broadcast-Multicast Services (BCMC) Parameters Message (BSPM) containing a full set of BSPM parameters pertaining to all active BCMC flows within a sector on an infrequent basis, smaller-sized differential or partial BSPMs are instead transmitted. Differential BSPMs contain updated information for existing flows or information for new flows, and because of their smaller size, can be transmitted more frequently than full BSPMs. A mobile terminal receiving a differential BSPM updates the flows with the information contained within the differential BSPM or adds the information contained within the differential BSPM for a new flow. Partial BSPMs divide the flow information contained in a large full BSPM over a plurality of smaller-sized partial BSPMs, which are separately and sequentially transmitted at different times. A mobile terminal receiving these partial BSPMs then reconstructs the full BSPM from a collection of received partial BSPMs.
    Type: Application
    Filed: March 22, 2004
    Publication date: September 22, 2005
    Inventors: Krishna Balachandran, Kenneth Budka, Arnab Das, Joseph Kang
  • Publication number: 20050180374
    Abstract: Information is transmitted over selected, Orthogonal Frequency Division Multiplexed (OFDM) sub-channels to avoid frequencies with unacceptable congestion, noise or interference levels. Using frequency hopping, selected non-contiguous OFDM sub-channels used for transmission may vary with time. Once a group of OFDM sub-channels is selected, a power level and modulation technique may also be selected based on channel quality.
    Type: Application
    Filed: February 17, 2004
    Publication date: August 18, 2005
    Inventors: Krishna Balachandran, Tingfang Ji, Joseph Kang, Wei Luo, Hsuan-Jung Su
  • Patent number: 6895057
    Abstract: A system and method is provided for communicating in a wireless communication system which supports link adaptation or link adaptation and incremental redundancy. The invention provides link adaptation at multiple code rate by dividing fixed length RLC blocks into coded sub-blocks. CRC code may be appended to the RLC blocks for error detection. The sub-blocks are then grouped into transmission units for transmission. The number of sub-blocks in each group is varied to provide multiple code rates. Headers are used to identify the transmission units being transmitted. In the case of retransmission, the transmission units may be expressly identified through extended headers. One or more of the originally transmitted sub-blocks are dropped and replaced by the extended headers in the retransmission. Accordingly, the present invention provides for a retransmission code rate which may be different from the code rate at which the transmission units were originally transmitted.
    Type: Grant
    Filed: November 2, 1999
    Date of Patent: May 17, 2005
    Assignee: Lucent Technologies Inc.
    Inventors: Krishna Balachandran, Richard P. Ejzak, Sanjiv Nanda
  • Publication number: 20050079867
    Abstract: A method of triggering registration of a mobile station in a network supporting broadcast multicast services employs registration triggers based on flow conditions and frequency conditions. For example, a registration message may be generated based on a change in frequency, from a first frequency to a second frequency, that is monitored by the mobile station. If the second frequency is not known to the network based on flow identifier information previously registered by the mobile station with the network, a registration to the network is triggered. By sending a registration, the network may page a mobile station on a single, given frequency, since the registration message indicates the mobile station's presence on that given frequency.
    Type: Application
    Filed: October 9, 2003
    Publication date: April 14, 2005
    Inventors: Krishna Balachandran, Kenneth Budka, Arnab Das, Joseph Kang
  • Publication number: 20050054331
    Abstract: Methods for signaling information to a group of users in a communication network supporting a broadcast-multicast service are described, in which one or more indicator bits of a sequence may be assigned to indicate transmission of signaling information that is related to the group. The sequence may be transmitted to the group on a first channel, with the signaling information related to the group being transmitted on a second channel.
    Type: Application
    Filed: September 4, 2003
    Publication date: March 10, 2005
    Inventors: Krishna Balachandran, Kenneth Budka, Arnab Das, Joseph Kang
  • Publication number: 20050054349
    Abstract: In a method of tracking a user in a communication network supporting a broadcast-multicast service, the network classifies groups of users into tracking areas. Movement of a user may be tracked as the user crosses a boundary between two tracking areas in the network. The method may enable a balance to be achieved between use of uplink overhead and the level or granularity of tracking desired, so as to conserve radio resources.
    Type: Application
    Filed: August 19, 2003
    Publication date: March 10, 2005
    Inventors: Krishna Balachandran, Kenneth Budka, Arnab Das, Michael Dolan, Joseph Kang
  • Publication number: 20040228353
    Abstract: A method and apparatus for providing differentiated quality of service (QoS) within a GPRS/EGPRS network environment. The invention advantageously uses one or more of a microscheduling technique, a peak picking technique and other techniques and methodologies to provide differentiated quality of service levels to users while maximizing total network throughput.
    Type: Application
    Filed: May 16, 2003
    Publication date: November 18, 2004
    Inventors: Krishna Balachandran, Kenneth C. Budka, Arnab Das, Oded Hauser, Wei Luo
  • Publication number: 20040230638
    Abstract: In a multiple node network, the method includes waking up at least one node from a sleep mode during at least one associated slot of a time-slotted frame, the sleep mode being a low power consumption mode. Also, in at least one node of a multiple node network, the period of time a node sleeps is based on the residual energy of the node, the residual energy of the nodes in the neighborhood, neighborhood node density, and combinations thereof.
    Type: Application
    Filed: May 1, 2003
    Publication date: November 18, 2004
    Inventors: Krishna Balachandran, Joseph H. Kang, Wing Cheong Lau
  • Publication number: 20040208183
    Abstract: A scheduler and a method for scheduling transmissions to a plurality of users in a communication network assigns a higher target minimum throughput for receiving a next transmission to a user based on a quality of service (QoS) class of the user. A token count that tracks the user's achieved performance relative to a target minimum throughput Is determined for each user in given timeslot, and a weight is determined for each user based on one or more of the token count and a current rate requested by the user. A user having the highest weight as determined by a weight function is scheduled to be served the next transmission. User priority for scheduling may be downgraded if an average data rate requested by the user is less than the target minimum throughput.
    Type: Application
    Filed: April 15, 2003
    Publication date: October 21, 2004
    Inventors: Krishna Balachandran, Kenneth C. Budka, Arnab Das, Kameswara Rao Medapalli, Minothi Parulekar
  • Publication number: 20040210619
    Abstract: A method for scheduling transmissions to a plurality of users in a communication network determines a satisfaction metric and a dissatisfaction metric for each user in a given timeslot that is to be used for a next scheduled transmission to one of the users. Each user is assigned a weight based on a value of at least one of the user's satisfaction metric, the user's dissatisfaction metric and a rate requested by the user. The use having the highest weight is selected to be served the next scheduled transmission in the given timeslot.
    Type: Application
    Filed: April 15, 2003
    Publication date: October 21, 2004
    Inventors: Krishna Balachandran, Kenneth C. Budka, Arnab Das, Kameswara Rao Medapalli, Minothi Parulekar
  • Publication number: 20040185864
    Abstract: In the method for selecting a channel rate, link quality between the serving portion of the network and a mobile station is determined from at least one signal strength measurement. A channel rate is then selected based on the determined link quality. Also, a physical channel is assigned to the mobile station on a prioritized basis with respect to the selected channel rate.
    Type: Application
    Filed: February 27, 2003
    Publication date: September 23, 2004
    Inventors: Krishna Balachandran, Tingfang Ji, Joseph H. Kang, James P. Seymour
  • Publication number: 20040171401
    Abstract: Systems and methods for intelligently assigning a channel to a device being used by a mobile user in a power controlled, wireless communications system by minimizing the difference between a mobile user's received signal power and the minimum received signal power of a current user on a candidate carrier frequency. Each carrier frequency within a cell is examined to determine whether it has at least one current user assigned to a channel and also has at least one unoccupied channel. For each carrier frequency that meets both of these requirements, a channel quality metric is obtained for each occupied channel. The carrier frequencies are pruned down to a subset of candidate carrier frequencies using the channel quality metrics. Finally, a channel within the set of candidate carrier frequencies is selected by computing a cost function based on the received signal power of the mobile user and the received signal power of each occupied channel.
    Type: Application
    Filed: February 28, 2003
    Publication date: September 2, 2004
    Inventors: Krishna Balachandran, Joseph H. Kang
  • Publication number: 20040160959
    Abstract: In a wireless communication system, there is a method of transmitting over a reverse link, where a medium access control layer multiplexes data from upper level layers onto transport channels that are used based on whether the user is in a scheduled transmission mode or an autonomous transmission mode. The transport channels may be mapped to one or more physical channels associated with a particular transport channel, based on whether the transport channel is dedicated for use in the scheduled or autonomous mode.
    Type: Application
    Filed: February 15, 2003
    Publication date: August 19, 2004
    Inventors: Krishna Balachandran, Arnab Das, Ashwin Sampath